Dyeing process



Patented July 26, 1932 UNITED STATES PATENT OFFICE WILLIAM ROYMOORHOUSE, OF NEW YORK, N. Y., ASSIGNOR T NATIONAL ANILINE & CHEMICALCOMPANY, INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK DYEINGPROCESS No Drawing.

textile fabrics by means of vat dyes.

There are three principal methods generally employed for dyeing cottonand rayon piece goods with vat dyes, namely: (1) working the material tobe dyed in a bath of the reduced dyestufl; (2) padding the material tobe dyed with the reduced dyestufl", and then developing the color byworking the padded material in a reducing bath; and (3) padding thematerial to be dyed with the unre-' duced dyestuft', and then workingthe padded material in a reducing bath, or jiggin it.

The dyeing of textile fabrics and bres with vat dyes by the third'method,'called the pad and jig method or the pigment padding method isdisclosed by Schlegel in United States Patents Nos. 893,384 and1,185,943. According to this process, the material to be dyed with thevat dyestuff (e. g. cotton fabric, yarn, and the like) is padded orprinted with a paste which contains the vat dyestuif in the unreducedform (pigment form), water, and a suitable thickener. It is then rolledup, either with or without drying, and transferred tothe jigger whereitis treated with a solution or suspension of an alkaline reducing agent(such as, for ex ample, alkaline hydrosulfite) in order to develop thecolor on the fibre. The material is then finished in any suitable mannere. g. by

passing it through oxidizing and soaping baths.

The present invention relates to improvements in the process of dyeingcotton and regenerated cellulose (rayon) piece goods and yarn bythe saidpadand jig method, and is especially concerned with improvements in thepadding process and the pading liquor.

One of the objects of the present invention.

v is the provision of a padding liquor which produces dyeings ofimproved strength and brightness of shade. v

Another object of the invention is the incorporation into a paddingliquor of a substance which increases the rapidity with which the vatdyestuff contained in the liquor is developed on the fibre on the jig.

Another object of the invention is the in- ,tions react alkaline.dyestufi' in the unreduced form, as used in Application filed February25, 1929. Serial No; 342,674.

corporation into a padding paste or liquor of a substance which enhancesthe smoothness of the paste and permits it to be more readily strained.

These and other objects of the invention will be apparent from aconsideration of the following disclosure which is given for the purposeof illustrating the invention.

According to the present invention, the material to be dyed with a vatdyestufi' is padded with a padding liquor which contains the vatdyestufi' in the unreduced form and an alkali metal salt whose aqueoussolu- The expression vat this description and in the claims, denotes thevat dyestufl as distinguished from its leucoderivatives.

It has been found, according to the present invention, if in dyeing bythe pad and jig method the material be padded with a padding liquorwhich contains a suitable alkalimetal salt whose aqueous solutions reactalkaline, that the dyeings obtained are of an improved quality, asindicated by the increased strength and brightness of shade of. thedyeings obtained with said liquor as compared with dyeings made underidentical conditions with a similar padding liquor which, however, doesnot contain said alkali-metal salt.

It has furthermore been found, according to the present invention, thatif into the padding liquor containing the vat dyestuff in the unreducedform there is incorporated a suitable alkali-metal salt whose aqueoussolutions react alkaline, the working qualities of the padding liquor orpaste are improved, as evidenced by the facts that the paste is smootherand can be strainedmore readily. In addition, when material padded witha padding liquor which contains such an alkalimetal salt is subjected tothe action of the reducing bath on the jig, the color is developed onthe fibre with greater rapidity than when said salt is not present.

In carrying out the process according, to a preferred method ofprocedure, a padding liquor is prepared containing a mixture of asuitable vat dyestufi in the unreduced form, a suitable alkali-metalsalt, water, and a suitdyestufl? employed, which may be, for example, ananthraquinone vat dye or an indigoid vat dye, is preferably used in thepaste form. Among the anthraquinone vat dyestuffs which are particularlyuseful in connection with the invention are the anthraquinone azine vatdyes; such as, indanthrone, flavanthrone, halogenated indanthrones, etc.

Among the alkali-metal salts suitable for incorporation into the paddingliquor, there may be mentioned, by Way of example, the alkallnealkali-metal salts of phosphoric acid, silicic acid, carbonic acid,hydrogen sulfide, and the like (such as, disodium and trisodiumphosphates, sodium silicate, sodium carbonate, potassium carbonate,sodium sulfide, ammonium sulfide, etc), the alkali-metal salts of thehigher fatty acids (such as, sodium stearate, sodium oleate, sodiumpalmitate, or their corresponding potassium salts), and the alkali-metalsalts of sulfonated fatty acids (such as, the sodium or ammonium saltsof sulfonated castor oil) and it will be understood that where in theclaims the expression an alkali-metal salt whose aqueous solutions reactalkaline is used, it meant to include the above salts and theirequivalent salts.

The invention will be described in connection with the followingexamples which are given for illustrative purposes only, it not beingintended to limit the procedure to the details given. I I

E trample 1.-A padding liquor is prepared containing the followingingredients in the following approximate amounts:

paste (Colour index No. 1113) 30 gms.

Trisodium phosphate 3g'ms.

' Gum tragacanth 3.6 gms.

Gum arabic 6.8 gms. Water suflicient to make up volume to approximately.1700 cc.

For example, by mixing the'dyestuflf with the sodium phosphate, which ispreferably in the form'of a water solution, adding the gum cloth of finemesh. Cotton piece goods is padded or printed with the liquor in asuit-' able manner known to the art (for example,

ployed in this example.

Example 2.Cot-ton cloth or yarn is padded in a padding liquor similar tothe one described in Example 1, with the difference, however, thatinstead of the trisodium phosphate, the liquor contains 1.6 grams ofsodium silicate. The padded cloth or yarn is subsequently treated as inExample 1.

Example 3.The procedure and ingredients are the same as in Example 1,with the exception that 1.5 grams of Turkey red oil (consisting mainlyof the sodium salt of sulfonated castor-oil) is employed instead of thetrisodium phosphate of said example.

E wample 4.Cotton piece goods is padded in a padding liquor containing80 grams of carbanthrene yellow G double paste (Colour index No. 1118)and 1.5 grams of a good grade of textile soap, such as Ivory soap,together with the gums and water in the proportions given in Example 1.The padded cloth is subsequently treated as above described.

Example 5.The procedure and ingredients are the same as in Example 4,with the exception that 1.5' grams of sodium carbonate is employedinstead of the soap of said example,

As pointed out above, the invention is not limited to the above specificexamples, but

broadly contemplates the incorporation into a padding liquor containingavat dyestufl' in unreduced form of a suitable alkali-meta. salt Whoseaqueous solutions react alkaline.

The vat dyestufls which are useful in the process are not limited tothose given in the above examples, but other suitable vat dyestuffs maybe employed; such as, other vat dyes of the anthraquinone series,including the indanthrones (particularly the halogenated indanthrones),fiavanthrones, dibenzanthrones, etc. The quantities of dyestuff to beused will obviously vary with the particular dyestuif employed and withthe shade and strength of color desired.

Instead of the alkali-metal salts used in the above examples, othersuitable alkalimetal salts whose aqueous solutions react alkaline may beused, as above indicated; such as, alkali-metal salts of the higherfatty acids and of the sulfonated fatty oils and fatty acids, alkalinealkali-metal salts of the polybasic inorganic acids, etc. And instead ofa single alkali-metal salt, mixtures of two or more of said salts may bealso employed. It will furthermore be evident that the salts need not bepure but that technical products may be used, and such technicalproducts may include mixtures of the alkali-metal salts of the fattyacids with some of the free fatty cent of trisodium phosphate ispreferred. It is to be noted, however, that within limits a' relativelysmall quantity of alkali-metal salt is preferred over a relatively largequantity;

' inasmuch as it has been found that instead of an improvement in thedyeings being effected, no improvement and even deleterious results areproduced when too large a quantity of alkali-metal salt is used. Forexample, the addition of too much alkali-metal salt often has been foundto cause the paste to-lump and the material to pad unevenly.

in the manner abpve described, but it will be' evident that it may beprepared in avariety of ways, and that the order of mixing theingr-edients may be suitably varied. While the procedure andtemperatures employed in the above examples are preferred,'it will beevident that they also can be varied.

I The process as described is an economical and rapid one. Dyeings ofbrighter and.

fuller shades are obtained than by the prior pad and jig processes. andthe development of the color on the jig is more rapid.

This application isa continuation in part of my copending application ISerial No. 294,586, filed July 21,- 1928, for dyeing process, andcontains sub ect matter specifically.

claimed in said application.

Having thus described my invention, what I claim and. desire to secureby Letters Patent is:

1. In a process of dyeing with a vat dyestuff by the pad and jig methodthe improvement which comprises padding the material to be dyed with apadding liquor which contains the vat dyestufi in the unreduced form, athickener and an alkali-metal salt whose aqueous solutions reactalkaline.

2. In a process of dyeing with a vat dyestuffby the pad and jig method,the improvement which comprises padding the material to be dyed with apadding liquor which contains the vatdyestuif in the unreduced form andan alkaline alkali-metal salt of an inor ganic polybasic acid.

3. In a process of dyeing with a vat-dyestuff by the pad and jig method,the improvement which comprises padding the material to be dyed with :1-padding liquor which contains the vat dyestufl in the unreduced form andtrisodium phosphate.

4. In a process of dyeing with a vat dyestuff by the pad and jig method,the improve- 'ment which comprises padding the material to be dyed witha padding liquor which contains the vat dyestuil in the unreduced formand an alkali-metal salt selected from the group consisting of trisodiumphosphate, so dium carbonate and sodium silicate.

5. In a process of dyeing with a vat dyestuff by the pad and jig method,the improvement which comprises padding the material to be dyed with apadding liquor which contains the vat dyestuif in the unreduced form, athickener, and an alkali-metal salt of a higher fatty acid.

6. In a process of dyeing with a vat dyestuff by the pad and jig method,the improvement which comprises padding the material to be dyed with apadding liquor which contains the vat dyestuif in the unreduced form, athickener, and an alkali metal salt stuff of the indigoid series by thepad and jig method, the improvement which comprises padding the materialto be dyed with a padding liquor which contains the vatdyestufi of theindigoid series in the unreduced form, a thickerfer, and an alkali-metalsalt whose aqueous solutions react alkaline.

9. In a processof dyeing with a vat dyestuif of the anthraquinone seriesby the pad and jig method, the improvement which comprises padding thematerial to be dyed with a padding liquor which contains the vatdyestufi' of the anthraquinone series in the unreduced form, a thickenerand an alkali-metal salt whose aqueous solutions react alkaline,

10. In a process of dyeing with an anthra quinone azine by the pad andjig method, the improvement which comprises paddinglthe material to bedyed with a padding liquor which contains the anthraquinone azine in theunreduced form, ,a thickener, and an alkali-metal salt whose aqueoussolutions react alkaline. 11. In a process of dyeing with an indanthroneby the pad and jig methodtheimprovement which comprises padding thematerial to be dyed with a padding l1quor which contains the indanthronein the unreduced form,

and an alkali-metal salt whose aqueous solutions react alkaline.

12. In a process of dyeing with a chlor-indanthrone by the pad and jigmethod, the improvement which comprises padding the material to be dyedwith a padding liquor which contains the chlorinated indanthrone in theunreduced form and an alkali-metal salt whose aqueous solutions reactalkaline.

13. In a process of dyeing with dichlorindanthrone by the pad and jigmethod, the improvement which comprises padding-the material to be dyedwith a padding liquor which contains dichlor-indanthrone in theunreduced form and triso'dium phosphate.

14. A padding liquor comprising a vat dyestuff substantially entirely inthe unreduced form, water, a thickener and an alkali-metal salt whoseaqueous solutions react alkaline.

15. A padding liquor comprising a vat dyestuif of the anthraquinoneseries substantially entirely in the unreduced form, water, a thickenerand an alkali-metal salt whose aqueous solutions react alkaline.

16. A padding liquor comprising an anthraquinone azine vat dyestuffsubstantially entirely in the unreduced form, water, a thickener and analkali-metal salt whose aqueous solutions react alkaline.

17. A padding liquor comprising an indanthrone substantially entirely inthe unreduced form, water and an alkali-metal salt whose aqueoussolutions react alkaline.

18. A padding liquor comprising a vat dyestuff of the indigoid seriessubstantially entirely'in the unreduced form, water and an alkali-metalsalt whose aqueous solutions react alkaline.

19. Material padded with the padding liquor of claim 14.

20. Material padded with the padding liquor of claim 15. a

21. Material padded with the padding liquor of claim 16. i

22. Material padded with the padding liqv. uor of claim 17.

23.' Material nor of claim 18.

In testimony whereof I aflix my signature.

WILLIAM ROY MOORHOUSE.

padded with the padding liq-

